Fluorescent pigments

ABSTRACT

Compounds of formula 
     
       
         A(B) x ,  (I) 
       
     
     wherein x is an integer from 1 to 4, 
     A is the radical of a chromophore of the quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine, phthalocyanine or azo series, which radical contains x N-atoms attached to B, preferably with at least one directly adjacent or conjugated carbonyl group, 
     B is a group of formula                    
      and, if x is 2, 3 or 4, may also be one, two or three hydrogen atoms. 
     The symbols Q, R 1 , R 2 , R 3 , R 4 , X, Y, Z, m and n, are as defined in claim 1. These carbamate group-containing soluble chromophores are distinguished by outstanding solid state fluorescence in the UV range as well as the by ease with which they can be converted to the corresponding pigments in the substrate in which they are incorporated.

This is a divisional of application Ser. No. 08/677,285 filed Jul. 7,1996 now U.S. Pat. No. 6,271,401, which is a divisional of applicationSer. No. 08/319,399 filed Oct. 6, 1994 now U.S. Pat. No. 5,561,232issued Oct. 1, 1996.

The present invention relates to novel soluble chromophores containingcarbamate groups, to their preparation and to the use thereof asfluorescent pigments and as pigment precursors which can be readilyconverted into the corresponding pigments.

N-substituted pyrrolo[3,4-c]pyrroles are disclosed in U.S. Pat. No.4,585,878 and 4,791,204. From the generic definition of all substituentsit can be inferred that the N-substituents may also be, inter alia,alkoxycarbonyl groups, which are defined in U.S. Pat. No. 4,791,204 asincluding methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl,n-butoxycarbonyl and n-hexyloxycarbonyl. U.S. Pat. No. 4,585,878 teachesthat the N-substituted pyrrolo[3,4-c]-pyrroles disclosed therein exhibithigh fluorescence in dissolved form in polymers.

The invention provides novel carbamate group-containing solublechromophores which, surprisingly, exhibit a very high solid statefluorescence, especially in the UV range, and which are readilyconvertible into the corresponding pigments with simultaneousdisplacement of the absorption spectrum, and hence open the way tounexpected applications.

Accordingly, the invention relates to compounds of formula

A(B)_(x),  (I),

wherein x is an integer from 1 to 4,

A is the radical of a chromophore of the quinacridone, anthraquinone,perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine,phthalocyanine or azo series, which radical contains x N-atoms attachedto B, preferably with at least one directly adjacent or conjugatedcarbonyl group,

B is a group of formula

and, if x is 2, 3 or 4, may also be one, two or three hydrogen atoms, inwhich formulae (II), (III) and (IV)

m, n and p are each independently of one another 0 or 1,

X is C₁-C₁₄alkylene or C₂-C₈alkenylene,

Y is a group —V—(CH₂)_(q)—,

Z is a group —V—(CH₂)_(r)—,

V is C₃-C₆cycloalkylene,

q is an integer from 1 to 6, and

r is an integer from 0 to 6,

R₁ and R₂ are each independently of the other hydrogen, C₁-C₆alkyl,C₁-C₄alkoxy, halogen, CN, NO₂, unsubstituted phenyl or phenoxy or phenylor phenoxy which are substituted by C₁-C₄alkyl, C₁-C₄alkoxy or halogen,

Q is hydrogen, CN, Si(R₁)₃,

 is a group C(R₅)(R₆)(R₇),

wherein R₅, R₆ and R₇ are each independently of one another hydrogen orhalogen and

 at least one of R₅, R₆ and R₇ is halogen,

 a group

wherein R₁ and R₂ are as defined above, a group SO₂R₈ or SR₈, wherein R₈is C₁-C₄alkyl,

 is a group CH(R₉)₂, wherein R₉ is unsubstituted phenyl or phenyl whichis substituted by C₁-C₄alkyl, C₁-C₄alkoxy or halogen,

or

is a group of formula

R₃ and R₄ are each independently of the other hydrogen, C₁-C₁₈alkyl, agroup

wherein X, Y, R₁, R₂, m and n are as defined above, or R₃ and R₄,together with the linking nitrogen atom, form a pyrrolidinyl,piperidinyl or morpholinyl radical.

A is the radical of a known chromophore having the basic structure

A(H)_(x),

for example

and all known derivatives thereof.

X in the significance of C₁-C₁₄alkylene is straight-chain or branchedalkylene, typically methylene, dimethylene, trimethylene,1-methylmethylene, 1,1-methylmethylene, 1,1-dimethyldimethylene,1,1-dimethyltrimethylene, 1-ethyldimethylene,1-ethyl-1-methyldimethylene, tetramethylene, 1,1-dimethyltetramethylene,2,2-dimethyltrimethylene, hexamethylene, decamethylene,1,1-dimethyldecamethylene, 1,1-diethyldecamethylene ortetradecamethylene.

X in the significance of C₁-C₈alkenylene is straight-chain or branchedalkenylene, typically vinylene, allylene, methallylene,1-methyl-2-butenylene, 1,1-dimethyl-3-butenylene, 2-butenylene,2-hexenylene, 3-hexenylene or 2-octenylene.

Halogen substituents may be iodo, fluoro, preferably bromo and, mostpreferably, chloro.

C₁-C₆Alkyl will typically be methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, n-amyl, tert-amyl, hexyl, andC₁-C₁₈alkyl may additionally be heptyl, octyl, 2-ethylhexyl, nonyl,decyl, dodecyl, tetradecyl, hexadecyl or octadecyl.

C₁-C₄Alkoxy is typically methoxy, ethoxy, n-propoxy, isopropoxy orbutoxy.

C₃-C₆Cycloalkylene is typically cyclopropylene, cyclopentylene and,preferably, cyclohexylene.

Particularly interesting compounds of formula I are those wherein x is 1or 2 and B is a group of formula

and, if x is 2, may also be one hydrogen atom, and in formulae IV, V andVI

m is 0 or 1,

X is C₁-C₄alkylene or C₂-C₅alkenylene,

R₁ and R₂ are each independently of the other hydrogen, C₁-C₄alkyl,methoxy, chloro or

NO₂, and

Q is hydrogen, CN, CCl₃, a group

 SO₂CH₃ or SCH₃,

R₃ and R₄ are each independently of the other hydrogen, C₁-C₄alkyl or agroup

or R₃ and R₄, taken together, form a piperidinyl radical,

and preferably those wherein x is 2 and B may be twice a group offormula

Preferred compounds of formula I are

a) perylenecarboximides of formula

wherein D is hydrogen, C₁-C₆alkyl, unsubstituted or halogen- orC₁-C₄alkyl-substituted phenyl, benzyl or phenethyl, or is B,

b) quinacridones of formula

wherein R₁₀ and R₁₁ are each independently of the other hydrogen,halogen, C₁-C₁₈alkyl, C₁-C₄alkoxy or phenyl,

c) dioxazines of formula

wherein R₁₂ is hydrogen, halogen or C₁-C₁₈alkyl,

d) isoindolines of formulae

wherein R₁₃ is a group

R₁₄ is hydrogen, C₁-C₁₈alkyl, benzyl or a group

R₁₅ has the same meaning as R₁₃,

R₁₆, R₁₇, R₁₈ and R₁₉ are each independently of one another hydrogen,C₁-C₁₈alkyl, C₁-C₄alkoxy, halogen or trifluoromethyl,

e) indigo derivatives of formula

wherein R₂₀ is hydrogen, CN, C₁-C₄alkyl, C₁-C₄alkoxy or halogen,

f) azobenzimidazolones of formula

wherein R₂₁ and R₂₂ are each independently of the other hydrogen,halogen, C₁-C₄alkyl or C₁-C₄alkoxy,

g) anthraquinoid compounds of formula

 and

h) phthalocyanines of formula

 wherein

X₁ is H₂, Zn, Cu, Ni, Fe or V,

X₂ is —CH(R₂₄)— or —SO₂—

R₂₃ is hydrogen, C₁-C₄alkyl, —N(E)R₂₄, —NHCOR₂₅, —COR₂₅ or

R₂₄ is hydrogen or C₁-C₄alkyl, R₂₅ is C₁-C₄alkyl and R₂₆ is hydrogen,halogen, C₁-C₄alkyl or C₁-C₄alkoxy,

z is 0 or 1 and y is an integer from 1 to 4,

in each of which formulae E is hydrogen or is B, with the proviso that Ein each formula is at least one group B and B is as defined above, inrespect of which definition the preferred meanings cited above apply.

Among the phthalocyanines, those of formula XVI, wherein X₁ is H₂, Cu orZn, X₂ is —CH₂— or —SO₂—, R₂₃ is hydrogen, —NHCOCH₃ or benzoyl and z is1, are preferred.

In U.S. Pat. No. 4,585,878 it is said in connection with the preparationof N-unsubstituted pyrrolpyrroles that they can be obtained by reactinga N-substituted pyrrolo-3,4-c-pyrrole with a compound that carries thecorresponding N-substituents as leaving groups in an organic solvent. Inthe sole Example describing a compound containing a N-carbonyl group(Example 9: N-benzoyl), 1,4-diketo-3,6-diphenyl-pyrrolo[3,4-c]pyrrole isreacted with benzoyl chloride. In the experiment to prepare the desiredcarbamates in analogous manner by reaction with a corresponding acidchloride derivative, it was unfortunately found that it was onlypossible to obtain said carbamates in poor yield.

Very surprisingly, however, it was observed that when using appropriatetrihaloacetates, azides, carbonates, alkylidene-iminooxyformates or, inparticular, appropriate dicarbonates, the desired carbamates areobtained in very good yield. An improved yield is also obtained—even ifonly to a lesser degree—by carrying out the reaction with an aliphaticacid chloride derivative, conveniently butyl chloroformate, in thepresence of a base as catalyst.

Accordingly, the invention further relates to a process for thepreparation of compounds of formula I, which comprises reacting acompound of formula

A(H)_(x),  (XVII)

wherein A and x are as defined above, in the desired molar ratio with adicarbonate of formula

B—O—B  (XVIII)

or with a trihaloacetate of formula

 (R₂₇)₃C—B  (XIX),

or with an azide of formula

BN₃  (XX),

or with a carbonate of formula

B—OR₂₈  (XXI),

or with an alkylidene-iminooxyformate of formula

wherein B is as defined above, R₂₇ is chloro, fluoro or bromo, R₂₈ isC₁-C₄alkyl or unsubstituted phenyl or phenyl which is substituted byhalogen, C₁-C₄alkyl, C₁-C₄alkoxy or —CN, R₂₉ is —CN or —COOR₁₈, and R₃₀is unsubstituted phenyl or phenyl which is substituted by halogen,C₁-C₄alkyl, C₁-C₄alkoxy or —CN, in an aprotic organic solvent and in thepresence of a base as catalyst, conveniently in the temperature rangefrom 0 to 400° C., preferably from 10 to 200° C., for 2 to 80 hours.

It is preferred to react the compound of formula XVII with a dicarbonateof formula XVIII.

The compounds of formula XVII, dicarbonates of formula XVIII,trihaloacetates of formula XIX, azides of formulae XX, carbonates offormula XXI and alkylidene-iminooxyformates of formula XXII are knownsubstances. Any that are novel can be prepared by methods analogous tostandard known ones.

The respective molar ratio of the compound of formula XVII and thecompounds of formulae XVIII-XXII will depend on the meaning of x, i.e.on the number of groups B to be introduced. Preferably, however, thecompounds of formulae XVIII-XXII will be used in a 2- to 10-fold excess.

Suitable solvents are typically ethers such as tetrahydrofuran ordioxane, or glycol ethers such as ethylene glycol methyl ether, ethyleneglycol ethyl ether, diethylene glycol monomethyl ether or diethyleneglycol monoethyl ether, and also dipolar aprotic solvents such asacetonitrile, benzonitrile, N,N-dimethylformamide,N,N-dimethylacetamide, nitrobenzene, N-methylpyrrolidone, halogenatedaliphatic or aromatic hydrocarbons such as trichloroethane, benzene oralkyl-, alkoxy- or halogen-substituted benzene, typically includingtoluene, xylene, anisole or chlorobenzene, or aromatic N-heterocyclessuch as pyridine, picoline or quinoline. Preferred solvents aretypically tetrahydrofuran, N,N-dimethylformamide andN-methylpyrrolidone. The cited solvents may also be used as mixtures. Itis convenient to use 5-20 parts by weight of solvent to 1 part by weightof reactant.

Bases suitable as catalysts are typically the alkali metals themselves,conveniently lithium, sodium or potassium and the hydroxides orcarbonates thereof, or alkali metal amides such as lithium, sodium orpotassium amide or alkali metal hydrides such as lithium, sodium orpotassium hydride, or alkaline earth metal or alkali metal alcoholateswhich are derived in particular from primary, secondary or tertiaryaliphatic alcohols of 1 to 10 carbon atoms, for example lithium, sodiumor potassium methylate, ethylate, n-propylate, isopropylate, n-butylate,sec-butylate, tert-butylate, 2-methyl-2-butylate, 2-methyl-2-pentylate,3-methyl-3-pentylate, 3-ethyl-3-pentylate, and also organic aliphaticaromatic or heterocyclic N-bases, typically includingdiazabicyclooctene, diazabicycloundecene and 4-dimethylaminopyridine andtrialkylamines such as trimethylamine or triethylamine. A mixture of thecited bases may also be used.

The organic nitrogen bases are preferred, for examplediazabicyclooctene, diazabicycloundecene and preferably,4-dimethylaminopyridine.

The reaction is preferably carried out in the temperature range from 10to 100° C., most preferably from 14 to 40° C., and under atmosphericpressure.

The novel compounds of formula I are admirably suitable for use asfluorescent pigments for the mass colouration of organic material ofhigh molecular weight.

Illustrative examples of high molecular weight organic materials whichcan be coloured with the novel compounds of formula I are vinyl polymerssuch as polystyrene, poly-α-methylstyrene, poly-p-methylstyrene,poly-p-hydroxystyrene, poly-p-hydroxyphenylstyrene, poly(methylacrylate)and poly(acrylamide) as well as the corresponding methacrylic compounds,poly(methylmaleate), poly(acrylonitrile), poly(methacrylonitile),poly(vinyl chloride), poly(vinyl fluoride), poly(vinylidene chloride),poly(vinylidene fluoride), poly(vinyl acetate), poly(methyl vinyl ether)and poly(butyl vinyl ether); novolaks derived from C₁-C₆aldehydes,typically formaldehyde and acetaldehyde, and a binuclear, preferablymononuclear, phenol which may be substituted by one or two C₁-C₉alkylgroups, one or two halogen atoms or a phenyl ring, for example o-, m- orp-cresol, xylene, p-tert-butyl phenol, o-, m- or p-nonylphenol,p-chlorophenol or p-phenylphenol, or from a compound containing morethan one phenolic group, e.g. resorcinol, bis(4-hydroxyphenyl)methane or2,2-bis(4-hydroxyphenyl)propane; polymers derived from maleimide and/ormaleic anhydride, e.g. copolymers of maleic anhydride and styrene;poly(vinylpyrrolidone), biopolymers and derivatives thereof such ascellulose, starch, chitine, chitosane, gelatin, zein, ethyl cellulose,nitrocellulose, cellulose acetate and cellulose butyrate; natural resinsand synthetic resins such as rubber, casein, silicone and siliconeresins, ABS, urea/formaldehyde and melamine/formaldehyde resins, alkydresins, phenolic resins, polyamides, polyimides, polyamide/imides,polysulfones, polyether sulfones, polyphenylene oxides, polyurethanes,polyureas, polycarbonates, polyarylenes, polyarylene sulfides,polyepoxides, polyolefins and polyalkadienes. Preferred high molecularweight organic materials are typically cellulose ethers and esters, forexample ethyl cellulose, nitrocellulose, cellulose acetate or cellulosebutyrate, natural resins or synthetic resins such as polymerisation orcondensation resins, for example aminoplasts, in particularurea/formaldehyde and melamine/formaldehyde resins, alkyd resins,phenolic plastics, polycarbonates, polyolefins, polystyrene, polyvinylchloride, polyamides, polyurethanes, polyesters, ABS, polyphenyleneoxide, rubber, casein, silicone and silicone resins, singly or inmixtures.

The above high molecular weight organic compounds may be singly or asmixtures in the form of plastic materials, melts or of spinningsolutions, paint systems, coating materials or printing inks. Dependingon the end use requirement, it is expedient to use the novel compoundsof formula I as toners or in the form of preparations.

The novel compounds of formula I are particularly suitable for the masscoloration of polyesters, polyvinyl chloride and, preferably,polyolefins such as polyethylene and polypropylene, as well as paintsystems, also powder coating compositions, printing inks and coatingmaterials.

The novel compounds of formula I can be used in an amount of 0.01 to 30%by weight, preferably 0.1 to 10% by weight, based on the high molecularweight organic material to be pigmented.

The pigmenting of the high molecular weight organic materials with thenovel compounds of formula I is conveniently effected by incorporating acompound of formula I by itself or in the form of a masterbatch in thesubstrates using roll mills, mixing or miling apparatus. The pigmentedmaterial is then brought into the desired final form by methods whichare known per se, conveniently by calendering, moulding, extruding,coating, casting or by injection moulding. It is often desirable toincorporate plasticisers into the high molecular weight compounds beforeprocessing in order to produce non-brittle mouldings or to diminishtheir brittleness. Suitable plasticisers are typically esters ofphosphoric acid, phthalic acid or sebacic acid. The plasticisers may beincorporated before or after blending the pigment salts of thisinvention into the polymers. To obtain different shades it is alsopossible to add fillers or other chromophoric components such as white,coloured or black pigments in any amount to the high molecular weightorganic materials in addition to the novel compounds of this invention.

For pigmenting paint systems, coating materials and printing inks, thehigh molecular weight organic materials and the novel compounds offormula I, together with optional additives such as fillers, otherpigments, siccatives or plasticisers, are finely dispersed or dissolvedin a common organic solvent or mixture of solvents. The procedure may besuch that the individual components by themselves, or also severalcomponents together, are dispersed or dissolved in the solvent andthereafter all the components are mixed.

When used for colouring, inter alia, polyvinyl chloride or polyolefinsor printing inks, the novel compounds of formula I have good allroundpigment properties, including good fastness to migration, light andweathering, and especially unexpectedly high fluorescence.

Of very great importance, however, is the entirely unexpected ease withwhich the soluble chromophores of this invention—even in the substratein which they have already been incorporated—can be converted to thecorresponding chromophore of formula A(H)_(x). This can be done in thesimplest manner, whether by thermal treatment (heating to thetemperature range from 50 to 400° C., preferably from 100 to 200° C. orlaser radiation), photolytic treatment (exposure to wavelengths belowe.g. 375 nm) or chemical treatment (with organic or inorganic acids orbases) of the solid materials, solutions or dispersions containing thenovel chromophores in organic or aqueous media, polymer solutions ormelts. These conversion methods can also be combined, thereby permittingthe coloration of paint systems, printing inks, especially for ink jetprinting, and plastics, also in fibre form, with unexpectedly enhancedproperties such as purity, colour strength, brilliance and transparency,as well as interesting applications in the analytical field.

It has even been found that the chemical treatment of specificchromophores of formula I with an organic or inorganic acid at 50 to180° C., preferably from 80 to 160° C., and subsequent cooling to about70 to 100° C., or the thermal treatment of said compounds by heating tothe temperature range from 180-350° C., can result in crystalmodifications of the corresponding chromophores of formula XVII.

The invention therefore additionally relates to a process for thecrystal modification of chromophores of formula XVII, comprising

a) the chemical treatment of a chromophore of formula I with an organicor inorganic acid at 50 to 180° C. and subsequent cooling,

or

b) the thermal treatment of a chromophore of formula I in thetemperature range from 180 to 350° C.

The invention is illustrated in more detail by the following Examples.

EXAMPLE 1

To a mixture of 1.8 g (0.00576 mol) of quinacridone and 0.3 g (0.00246mol) of 4-dimethylaminopyridine in 90 ml of N,N-dimethylformamide areadded 6.0 g (0.0275 mol) of di-tert-butyldicarbonate. The resultantviolet suspension is stirred overnight at room temperature, with theexclusion of atmospheric moisture. The colour changes toyellowish-orange. Afterwards, the reaction mixture is poured, withstirring, into 100 ml of distilled water. The yellow precipitate isisolated by filtration and the residue is washed with distilled waterand dried, affording 2.8 g (95% of theory) of the product of formula

Analysis: ¹H-NMR(CDCl₃): 8.74 (s, 2H); 8.41 (d, 2H); 7.84 (d, 2H); 7.72(t, 2H); 7.38 (t, 2H); 1.75 (s, 18H).

EXAMPLE 2

To a suspension of 10.31 g (0.0393 mol) of indigo and 2.79 g (0.0228mol) of 4-dimethylaminopyridine in 150 ml of N,N-dimethylformamide areadded, in two portions, 45.31 g (0.2076 mol) ofdi-tert-butyldicarbonate. The mixture is stirred for 20 hours at roomtemperature, during which time the colour changes from dark blue toviolet. The product is isolated by filtration and the residue is washedfirst with 20 ml of dimethyl formamide, then with distilled water, anddried, affording 9.79 g of a brilliant red solid. An additional 5.13 gof product is obtained by diluting the filtrate with distilled water.The total yield is 14.93 g (82.1% of theory) of a product of formula

Analysis: ¹H-NMR(CDCl₃): 8.02 (d, 2H); 7.76 (d, 2H); 7.61 (t, 2H); 7.21(t, 2H); 1.62 (s, 18H).

EXAMPLE 3

To a mixture of 1.5 g (0.00337 mol) of the pigment of formula

and 9.7 g (0.0444 mol) of di-tert-butyldicarbonate in 80 ml ofN,N-dimethylacetamide is added 0.18 g (0.00147 mol) of4-dimethylaminopyridine. The resultant suspension is stirred for 24hours at room temperature. The reaction mixture is then poured, withsting, into 200 ml of distilled water. The yellow precipitate isisolated by filtration and the residue is washed with distilled waterand dried at room temperature under vacuum, affording 2.71 g (95% oftheory) of a product of formula

Analysis: ¹H-NMR(CDC₃): 8.22 (d, 2H); 7.83 (d, 2H); 7.72 (t, 2H); 7.63(t, 2H); 7.56 (d, 2H); 7.42 (d, 2H); 1.45 (s, 36H).

EXAMPLE 4

To a mixture of 1.4 g (0.0037 mol) of a monoazopigment of formula

and 2.67 g (0.01221 mol) of di-tert-butyldicarbonate in 50 ml ofN,N-dimethylacetamide are added 0.2 g (0.00164 mol) of4-dimethylaminopyridine. The reaction mixture is stirred for 48 hours atroom temperature, during which time an orange suspension forms. Theyellow precipitate is then isolated by filtration and the residue iswashed with a small amount of N,N-dimethylacetamide and afterwards withdistilled water and dried at room temperature under vacuum, affording0.67 g (31% of theory) of a product of formula

Analysis: ¹H-NMR(CDCl₃): 15.9 (s, br, 1H); 11.17 (s, br, 1H); 7.94 (d,1H); 7.90 (s, 1H); 7.85 (d, 1H); 7.64 (d, 1H); 7.06-7.04 (m, 2H); 2.65(s, 3H); 2.35 (s, 3H); 2.32 (s, 3H); 1.64 (s, 9H).

EXAMPLE 5

0.07 g of the product of Example 1 are heated in a test tube for 10minutes at 180° C. All analytical data obtained for the resultant violetpowder are in accord with those of the pure quinacridone of formula

The conversion yield is 99%.

EXAMPLE 6

0.07 g of the product of Example 3 are dissolved in 1 ml of acetone andthe solution is then added all at once to 1 ml of 33% HCl. Allanalytical data obtained for the resultant red powder are in accord withthose of the pure pigment of formula

The conversion yield is 99%.

EXAMPLES 7-10

In accordance with the general procedure described in Example 1, thecompounds of formula

listed in the following Table can be obtained using correspondingdicarbonates.

Reaction- Example E Solvent time Yield Colour 7

DMF 30 h 80% yellowish orange 8

DMF 24 h 30% yellowish orange 9

DMF 16 h 80% yellowish orange 10

DMF 24 h 35% yellowish orange DMF = dimethyl formamide

EXAMPLE 11

To a suspension of 1.03 g of the product of Example 1 in 30 ml ofN,N′-dimethylformamide and 10 ml of water are added 4 ml oftrifluoroacetic acid. The mixture is heated to 105° C., stirred for 2hours at this temperature and then chilled on an ice-bath to 20° C. Theprecipitated pigment is isolated by filtration, washed with methanol andthen with water and dried at 60° C. under vacuum, affording 0.59 g ofred powder. The X-ray diffraction pattern is characterised by thefollowing diffraction lines:

Interplanar spacing Two-fold hue angle (d values in Å) (2Θ) Relativeintensity 15.0530 5.87 100 7.5164 11.76 45 5.5635 15.92 27 4.0350 22.0121 3.7534 23.69 9 3.2870 27.11 61 2.9988 29.77 5 2.3129 38.91 5(β-modificadon of quinacridone).

EXAMPLE 12

A mixture of 4.75 g of toluene-4-sulfonic acid and 100 ml of diphenylether is heated to 150° C. To the solution so obtained is then added asolution of 1.03 g of the product of Example 1 in 150 ml oftetrahydrofuran over 5 hours at 150° C. The tetrahydrofuran whichevaporates rapidly under these reaction conditions is condensed in aLiebig condenser and collected in a receiver. The reaction mixture isstirred for a further 2 hours at 150° C. and then cooled to 60° C. Theprecipitated pigment is isolated by filtration, washed with methanol andafterwards with water and dried under vacuum at 60° C., affording 0.67 gof a red powder.

The The X-ray diffraction pattern is characterised by the followingdiffraction lines:

Interplanar spacing Two-fold hue angle (d-values in Å) (2Θ) Relativeintensity 13.6841 6.45 100 6.7972 13.01 43 6.6153 13.37 52 6.4440 13.7384 5.5678 15.91 5 5.2536 16.86 10 4.3559 20.37 14 3.7526 23.69 14 3.563224.97 11 3.3796 26.35 66 3.3583 26.52 55 3.2065 27.80 7 3.1306 28.49 72.9534 30.24 6 2.4576 36.53 5 2.2135 40.73 7 (γ-modification ofquinacridone).

What is claimed is:
 1. A compound the basic structure of which is offormula

wherein B is a group of formula

m, n and p are each independently of one another 0 or 1, X is branchedC₂-C₁₄alkylene or C₂-C₈alkenylene, Y is a group —V—(CH₂)_(q)—, Z is agroup —V—(CH₂)_(t)—, V is C₃-C₆cycloalkylene, q is an integer from 1 to6, and r is an integer from 0 to 6, R₁ and R₂ are each independently ofthe other hydrogen, C₁-C₆alkyl, C₁-C₄alkoxy, halogen, CN, NO₂,unsubstituted phenyl or phenoxy or phenyl or phenoxy which aresubstituted by C₁-C₄alkyl, C₁-C₄alkoxy or halogen, Q is hydrogen, CN,Si(R₁)₃;  a group C(R₅)(R₆)(R₇), wherein R₅, R₆ and R₇ are eachindependently of one another hydrogen or halogen and at least one of R₅,R₆ and R₇ is halogen;  a group

 wherein R₁ and R₂ are as defined above;  a group SO₂R₈ or SR₈, whereinR₈ is C₁-C₄alkyl;  a group CH(R₉)₂, wherein R₉ is unsubstituted phenylor phenyl which is substituted by C₁-C₄alkyl, C₁-C₄alkoxy or halogen; or a group of formula

R₃ and R₄ are each independently of the other hydrogen, C₁-C₁₈alkyl, agroup

wherein X′ is C₁-C₁₄alkylene or C₂-C₁₈alkenylene, and wherein Y, R₁, R₂,m and n are as defined above, or R₃ and R₄, together with the linkingnitrogen atom, form a pyrrolidinyl, piperidinyl or morpholinyl radical,and with the proviso that when B is a group of formula (III) whereinboth m and n are 0, Q is not hydrogen.
 2. A compound according toformula (Ib) according to claim 1, wherein B is a group of formula

and in formulae IV, V and VI, m is 0 or 1, X is branched C₂-C₄alkyleneor C₂-C₄alkenylene, R₁ and R₂ are each independently of the otherhydrogen, C₁-C₄alkyl, methoxy, chloro or NO₂, and Q is hydrogen, CN,CCl₃, a group a group

 SO₂CH₃ or SCH₃, R₃ and R₄ are each independently of the otherC₁-C₄alkyl or a group

or R₃ and R₄, taken together, form a piperidinyl radical, and with theproviso that when B is a group of formula (VI) wherein both m is 0, Q isnot hydrogen.
 3. A compound according to formula (Ib) according to claim1, wherein B is a group of formula

and in formulae V and VI, m is 0 or 1, X is branched C₂-C₄alkylene orC₂-C₅alkenylene, R₁ and R₂ are each independently of the other hydrogen,C₁-C₄alkyl, methoxy, chloro or NO₂, and Q is hydrogen, CN, CCl₃, a groupa group

 SO₂CH₃ or SCH₃, and with the proviso that when B is a group of formula(VI) wherein both m is 0, Q is not hydrogen.
 4. A compound according toformula (Ib) according to claim 1, wherein B is a group of formula


5. A compound according to claim 1 wherein m is 1 and X is branchedC₄-C₁₄alkylene.
 6. A compound according to claim 5 wherein X selectedfrom 1,1-dimethylmethylene, 1,1-dimethyldimethylene,1,1-dimethyltrimethylene, 1-ethyldimethylene,1-ethyl-1-methyldimethylene, 1,1-dimethyltetramethylene,2,2-dimethyltrimethylen, 1,1-dimethyldecamethylene, and1,1-diethyldecamethylene.
 7. A compound according to claim 1 wherein mis 1 and X is branched C₄-C₈alkenylene.
 8. A compound according to claim7 wherein X is selected from 1-methyl-2-butylene and1,1-dimethyl-3-butenylene.